Ink composition comprising a block or graft polymer and at least one colorant

ABSTRACT

Disclosed herein are a functional-substance-including structured material having good dispersion stability, and an ink composition, which inhibits aggregation by interaction between particles, and has stable dispersibility in a solvent and good coloring ability and fixing ability. The functional-substance-including structured material comprises a plurality of functional substances different from each other physically included in a block polymer or graft polymer. The ink composition comprises the functional-substance-including structured material, and a solvent or dispersing medium.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a functional substance includingstructured material containing a polymer, which can be used as variousfunctional materials, a functional substance dispersed compositioncontaining the structured material, and a liquid-applying process andapparatus for applying the composition.

2. Related Background Art

As for dispersed materials containing a functional substance, haveheretofore been well known agricultural chemicals such as herbicides andinsecticides, medicaments such as anti-cancer drugs, anti-allergic drugsand antiphlogistics, and coloring materials containing a colorant asparticulate solids, such as inks and toners. In recent years, amongthese, digital printing technology utilizing a composition containing acoloring material has been vigorously developed. Typical examples ofthis digital printing technology include those calledelectrophotographic technology and ink-jet technology, and itsimportance-as image-forming technology in homes and offices has more andmore increased in recent years.

Among these, the ink-jet technology has a great feature as a directlyrecording method that it is compact and low in consumption power. Theformation of high-quality images is also quickly advanced by formationof micro-nozzles or the like. An example of the ink-jet technologyincludes a method that an ink fed from an ink tank is evaporated andbubbled by heating it by a heater in a nozzle, thereby ejecting the inkto form an image on a recording medium. Another example includes amethod that an ink is ejected from a nozzle by vibrating a piezoelectricelement.

In order to improve weathering resistance and fixing ability, it isinvestigated to use pigment-dispersed inks as inks for ink-jet. U.S.Pat. No. 5,085,698 has proposed a method that a pigment is dispersed byan ionic block polymer having at least one hydrophilic component and atleast one hydrophobic component. However, a further improvement isdesired in point of inhibiting aggregation by interaction betweenparticles to stably disperse the pigment in a solvent over a long periodof time and from the viewpoints of tint, coloring ability and fixingability.

SUMMARY OF THE INVENTION

The present invention has been completed in view of such problems in thebackground art, and has as its object the provision of a functionalsubstance including structured material having good dispersion stabilitywith a plurality of different functional substances included in apolymer.

Another object of the present invention is to provide a functionalsubstance dispersed composition, in particular, an ink compositioncomprising the structured material and a solvent, which inhibitsaggregation by interaction between particles, and has stabledispersibility in the solvent and good coloring ability and fixingability.

The above objects can be achieved by the present invention describedbelow.

In a first aspect of the present invention, there is thus provided afunctional substance including structured material comprising aplurality of functional substances different from each other physicallyincluded in a block polymer or graft polymer.

The plurality of the functional materials may preferably be included ina micelle formed by the block polymer or graft polymer.

In a second aspect of the present invention, there is also provided afunctional substance dispersed composition comprising the functionalsubstance including structured material, and a solvent or dispersingmedium.

In a third aspect of the present invention, there is further provided aliquid-applying process comprising the step of applying the functionalsubstance dispersed composition to a medium.

In a fourth aspect of the present invention, there is still furtherprovided a liquid-applying apparatus comprising a liquid-applying meansfor applying the composition by causing energy for application to act onthe functional substance dispersed composition, and a driving means fordriving the liquid-applying means.

According to the present invention, there can be provided a functionalsubstance including structured material having good dispersion stabilityin which a plurality of functional substances different from each otherare included in a polymer.

According to the present invention, there can also be provided afunctional substance dispersed composition, in particular, an inkcomposition comprising the structured material and a solvent, whichinhibits aggregation by interaction between particles, and has stabledispersibility in the solvent and good coloring ability and fixingability.

According to the present invention, there can further be provided aliquid-applying process and apparatus, by which the composition can bestably ejected.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 schematically illustrates the mechanism of an ink-jet recordingapparatus according to the present invention.

FIG. 2 typically illustrates an ink-jet head kit according to thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will hereinafter be described in detail.

In the first aspect of the present invention, there is provided afunctional substance including structured material (hereinafter referredto as “structured material” merely) comprising a plurality of functionalsubstances different from each other included in a block polymer orgraft polymer.

The term “functional substance” as used in the present invention means acompound or composition exhibiting a desired function. As examplesthereof, may be mentioned agricultural chemicals such as herbicides andinsecticides, medicaments such as anti-cancer drugs, anti-allergic drugsand antiphlogistics, and coloring materials, typically, dyes andpigments. Examples of the agricultural chemicals include activecompounds having a herbicidal effect and active compounds having aninsecticidal effect. Examples of the medicaments include compounds whichease or remit an objective condition. Examples of the coloring materialsused include particulate solids such as pigments, and dye compounds.

In the present invention, the coloring materials are preferably used asthe functional substances. As described above, examples of the coloringmaterials include pigments. Examples of the pigments include inorganicachromatic pigments and organic or inorganic chromatic pigments.Colorless or light-colored pigments and metalescent pigments may also beused. In the present invention, newly synthesized pigments may also beused.

Examples of commercially available pigments of black, cyan, magenta andyellow are mentioned below.

As examples of black pigments, may be mentioned Raven 1060 (trade name,product of Columbian Carbon Co.), MOGUL-L (trade name, product of CabotCompany), Color Black FW1 (trade name, product of Degussa AG) and MA100(trade name, product of Mitsubishi Chemical Corporation). However, thepresent invention is not limited thereto.

As examples of cyan pigments, may be mentioned C.I. Pigment Blue-15:3,C.I. Pigment Blue-15:4 and C.I. Pigment Blue-16. However, the presentinvention is not limited thereto.

As examples of magenta pigments, may be mentioned C.I. Pigment Red-122,C.I. Pigment Red-123 and C.I. Pigment Red-146. However, the presentinvention is not limited thereto.

As examples of magenta pigments, may be mentioned C.I. Pigment Red-122,C.I. Pigment Red-123 and C.I. Pigment Red-146. However, thepresent-invention is not limited thereto.

As examples of yellow pigments, may be mentioned C.I. Pigment Yellow-74,C.I. Pigment Yellow-128 and C.I. Pigment Yellow-129. However, thepresent invention is not limited thereto. In the present invention, dyesmay also be used like the pigments.

The dyes used in the present invention may be either publicly known ornovel, and such water-soluble dyes such as direct dyes, acid dyes, basicdyes, reactive dyes and food dyes, fat-soluble (oil-soluble) dyes, andinsoluble colorants such as disperse dyes as described below may beused. These dyes may also be used in a solid state. Regarding this, forexample, oil-soluble dyes are preferably used.

Examples of the water-soluble dyes include direct dyes such as C.I.Direct Black 17, 62 and 154; C.I. Direct Yellow 12, 87 and 142; C.I.Direct Red 1, 62 and 243; C.I. Direct Blue 6, 78 and 199; C.I. DirectOrange 34 and 60; C.I. Direct Violet 47 and 48; C.I. Direct Brown 109;and C.I. Direct Green 59,

acid dyes such as C.I. Acid Black 2, 52 and 208; C.I. Acid Yellow 11, 29and 71; C.I. Acid Red 1, 52 and 317; C.I. Acid Blue 9, 93 and 254; C.I.Acid Orange 7 and 19; and C.I. Acid Violet 49,

reactive dyes such as C.I. Reactive Black 1, 23 and 39; C.I. ReactiveYellow 2, 77 and 163; C.I. Reactive Red 3, 111 and 221; C.I. ReactiveBlue 2, 101 and 217; C.I. Reactive Orange 5, 74 and 99; C.I. ReactiveViolet 1, 24 and 38; C.I. Reactive Green 5, 15 and 23; and C.I. ReactiveBrown 2, 18 and 33, and

C.I. Basic Black 2; C.I. Basic Red 1, 12 and 27; C.I. Basic Blue 1 and24; C.I. Basic Violet 7, 14 and 27; and C.I. Food Black 1 and 2.

As examples of the oil-soluble dyes, are mentioned the followingcommercially available products of various colors.

As examples of oil-soluble dyes of black, may be mentioned C.I. SolventBlack 3, 22:1 and 50. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of yellow, may be mentioned C.I. SolventYellow 1, 25:1 and 172. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of orange, may be mentioned C.I. SolventOrange 1, 40:1 and 99. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of red, may be mentioned C.I. SolventRed 1, 111 and 229. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of violet, may be mentioned C.I. SolventViolet 2, 11 and 47. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of blue, may be mentioned C.I. SolventBlue 2, 43 and 134. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of green, may be mentioned C.I. SolventGreen 1, 20 and 33. However, the present invention is not limitedthereto.

As examples of oil-soluble dyes of brown, may be mentioned C.I. SolventBrown 1, 12 and 58. However, the present invention is not limitedthereto.

The examples of the coloring materials mentioned above are particularlypreferred in the structured material according to the present invention.However, the coloring materials used in the present invention are notlimited to the coloring materials mentioned above.

In the structured material according to the present invention, aplurality of functional substances characteristically different fromeach other are used as the functional substances. The term “plurality ofdifferent functional substances” means a plurality of functionalsubstances except the case where one functional substance of the sametype is used, for example, a combined use of at least two functionalsubstances of the same or different types. For example, in the casewhere a plurality of substances of the same or different types arecoloring materials, a combination of an oil-soluble dye A and anotheroil-soluble dye B, and a combination of a pigment C and a dye D may bementioned as functional substances of the same type and as functionalsubstances of different types, respectively.

As a feature of the present invention, the plurality of the functionalsubstances are physically included in a block polymer or graft polymer.A preferred form of such inclusion in the block polymer or graft polymeris a form on inclusion in micelles formed by such a polymer. Theinclusion of the plurality of the functional substances, preferablycoloring materials, in the polymer permits stabilizing thedispersibility and functionality of the respective functional substancesdifferent in nature. A preferred embodiment of the present inventionincludes a structured material, in which a plurality of coloringmaterials are included. The use of the plurality of the coloringmaterials permits controlling tint while realizing excellent dispersionstability. The composition according to the present invention that isphysically included is very preferred in that the plurality of thefunctional substances can be simply subjected to a dispersing andincluding treatment as described below. In some cases, the functionalsubstances or the functional substance and the polymer may be in a statechemically bonded to each other. However, this requires to form achemical bond of these substances, and so it can be said that thepresent invention is a superb method in productivity from the industrialpoint of view.

As described above, the oil-soluble dyes may be used in the presentinvention. In this case, the dispersion stability can be more improvedby causing the plurality of the coloring materials to coexist, which isthe feature of the present invention. Combinations of an oil-soluble dyeand a pigment, and an oil-soluble dye and another oil-soluble dye arepreferably considered. In the case of coloring materials of the samehue, such a combination may be mentioned as a preferred embodiment inthat dispersion stability is improved, and color characteristics can bemore precisely controlled. In the case of coloring materials ofdifferent hues, color expression of other special color systems thanfundamental three colors of a primary or complementary color system isallowed. In addition, it can be realized to permit a variety ofdevelopments of the color expression without sacrificing the dispersionstability, in the form improved on the contrary. A preferred embodimentthat can exhibit these features or merits may include a combination of apigment and an oil-soluble dye. This is a combination of a pigment andan oil-soluble dye of the same hue or different hues that dispersionstability can be improved, color characteristics can be more preciselycontrolled, and a variety of developments of color expression can berealized without sacrificing the dispersion stability, rather in theform which can improve the dispersion stability. In the presentinvention, as a preferred process of including these coloring material,may be used a process of dispersing or dissolving coloring materials inan organic solvent, mixing the dispersion or solution with a polymerdissolved likewise and inverting the resultant mixture into a waterphase. At this time, the use of the combination of the pigment and theoil-soluble dye can exhibit such a new merit that the dispersibility ofthe pigment that can not sufficiently be included nor dispersed can beimproved by the use of the oil-soluble dye in combination. The presentinvention is can be said to be industrially very useful in this sense.The oil-soluble dyes in the present invention mean dyes soluble in anorganic solvent and are called fat-soluble dyes.

From the viewpoint of such inclusion of the plurality of the coloringmaterials, an amphiphilic polymer which forms a block polymer or graftpolymer develops a good included state, i.e., good dispersion stabilitybecause it has stable polymer micelle-forming ability. The stability ofthe dispersed state is ensured by the presence of the plural kinds ofcoloring materials in the polymer. For example, when a single type ofcoloring material is used, crystals tend to grow in a micelle core whenthe coloring material is an oil-soluble dye in particular, and so thedispersion stability may be impaired in some cases. The use of pluralkinds of coloring materials permits successfully inhibiting such crystalgrowth and well developing the effects described above. According to thepresent invention, coloring materials, which have heretofore been unableto be used due to their poor dispersion stability though they have goodproperties, can be made useful by including them together with othercoloring materials in the block polymer or graft polymer. As thepolymer, a block polymer is preferred in that uniform micelles can beformed.

As the block polymer or graft polymer used, a polymer containing apolyvinyl ether unit structure and having a low glass transitiontemperature and high molecular mobility is very preferred from theviewpoint of ensuring the above-described dispersion stability.

A polyvinyl ether polymer obtained by a cationic living polymerizationprocess is preferably used in that more stable polymer micelle can beformed from the viewpoint of a precise control of molecular weight aswell as molecular weight distribution.

The total content of the plural kinds of functional substances containedin the structured material according to the present invention ispreferably from 0.01% by weight to 80%. by weight based on the totalweight of the structured material. When the content of the functionalsubstances falls within the range of from 0.01% by weight to 80% byweight, a sufficient function is achieved, and the dispersibilitybecomes good. The content is preferably within a range of from 0.1% byweight to 80% by weight, more preferably from 0.3% by weight to 70% byweight.

The respective proportions of the plural kinds of the functionalsubstances used in the present invention are optional. However, theproportion of each functional substance used is at least 0.1% by weight,preferably at least 1% by weight based on the total weight of thefunctional substances.

The block polymer characteristically used in the present invention isalso called a block copolymer and is a polymer that polymers havingdifferent segment structures are linearly bonded to each other by acovalent bond. The graft polymer used in the present invention is apolymer that another polymer is chemically boned in a branched form to alinear polymer that becomes a backbone.

The block polymer that is a component characteristically used in thepresent invention will hereinafter be described. Specific examples ofblock polymers usable in the present invention include acrylic ormethacrylic block polymers, block polymers composed of polystyrene andany other addition polymerization system or condensation polymerizationsystem, and block polymers having polyoxyethylene or polyoxyalkyleneblocks. These heretofore known block polymers may be used. In thepresent invention, the block polymer is more preferably in a block formof AB, ABA, ABD or the like. A, B and D indicate block segmentsdifferent from one another. The block polymer used in the presentinvention is preferably amphiphilic. As a specifically preferable formof the block polymer, is preferably used an AB diblock polymer composedof a hydrophobic segment and a hydrophilic segment having an organicacid unit or a unit of an ionic salt thereof, or an ABC triblock polymercomposed of a hydrophobic segment, a hydrophilic segment having anorganic acid unit or a unit of an ionic salt thereof and a furthersegment. In the form of the ABC triblock polymer, a form that A is ahydrophobic segment, B is a nonionic hydrophilic segment, and C is ahydrophilic segment having an organic acid unit or a unit of an ionicsalt thereof is preferably used from the viewpoint of stabilization ofan included state.

In the present invention, the block polymer may be a graft polymer thatanother polymer is chemically boned in a branched form to a linearpolymer that becomes a backbone. The respective segments of the blockpolymer may be copolymer segments. The form of the copolymer is notlimited, but may be either a random segment or a graduation segment. Inthe present invention, a block polymer containing a polyalkenyl etherstructure is preferably used. A block polymer having a polyvinyl etherstructure is particularly preferably used. A great number of syntheticprocesses of the block polymer containing the polyalkenyl etherstructure have been reported. A process by cationic livingpolymerization by Aoshima et al. (Journal of Polymer Bulletin, Vol. 15,p. 417, 1986; Japanese Patent Application Laid-Open No. 11-322942) isrepresentative thereof. By conducting polymer synthesis by the cationicliving polymerization, various polymers such as homopolymers, copolymerscomposed of two or more monomers, block polymers, graft polymers andgraduation polymers can be synthesized with their chain lengths(molecular weights) exactly made uniform. In the polyalkenyl ether,various functional groups may be introduced in its side chains. Besides,the cationic polymerization may-also be conducted in a HI/I₂ system,HCl/SnCl₄ system or the like.

The structure of the block polymer containing the polyalkenyl etherstructure may be a copolymer composed of vinyl ether and anotherpolymer.

The block polymer containing the polyvinyl ether structure preferablyused preferably has a repeating unit structure represented by thefollowing general formula (1).

In the general formula (1), R¹ is selected from a linear, branched orcyclic alkyl group having 1 to 18 carbon atoms,—(CH(R²)—CH(R³)—O)_(l)—R⁴ and —(CH₂)_(m)—(O)_(n)—R⁴ in which l and mare, independently of each other, selected from integers of from 1 to12, n is 0 or 1, R² and R³ are, independently of each other, H or —CH₃,and R⁴ is H, a linear, branched or cyclic alkyl group having 1 to 6carbon atoms, Ph, Pyr, Ph-Ph, Ph-Pyr, —CHO, —CH₂CHO, —CO—CH═CH₂,—C0-C(CH₃)═CH₂ or —CH₂COOR⁵, with the proviso that hydrogen bonded tocarbon may be substituted by a linear or branched alkyl group having 1to 4 carbon atoms, F, Cl or Br when R⁴ is any other group than hydrogen,and carbon in the aromatic ring may be substituted by nitrogen, and R⁵is H or an alkyl group having 1 to 5 carbon atoms.

In the present invention, -Ph, -Pyr, -Ph-Ph and -Ph-Pyr denote phenyl,pyridyl, biphenyl and pyridylphenyl groups, respectively. With respectto the pyridyl, biphenyl and pyridylphenyl groups, they may be anypossible position isomers.

In the present invention, an amphiphilic block polymer is preferablyused. It can be obtained by, for example, conducting synthesis byselecting a hydrophobic block segment and a hydrophilic block segmentfrom the repeating unit structures of the general formula (1).

Examples of the structure of a vinyl ether monomer as the repeating unitstructure of the polyvinyl ether structure of the block polymer arementioned below. However, the polyvinyl ether structures used in thepresent invention are not limited thereto.

In the formulae, Me, Et and i-Pr denote methyl, ethyl and isopropylgroups, respectively.

Examples of the structure of the polyvinyl ether composed of each ofthese vinyl ether monomers are mentioned below. However, the polymersused in the present invention are not limited thereto.

In the polyvinyl ether, the numbers u and v of repeating units are,independently of each other, preferably from 1 to 10,000, and the total(u+v) thereof is preferably from 10 to 20,000.

The molecular weight distribution Mw (weight average molecularweight)/Mn (number average molecular weight) of the block polymer usedin the present invention is preferably at most 2.0, more preferably atmost 1.6, still more preferably at most 1.3, still further preferably atmost 1.2. The number average molecular weight (Mn) of the block polymerused the present invention is preferably within a range of from 1,000 to300,000. When the number average molecular weight of the block polymerused in the present invention falls within the range of from 1,000 to300,000, substances respectively exhibiting predetermined functions canbe dispersed in a solvent with good results.

In order to improve dispersion stability and inclusion property, themolecular mobility of the block polymer is preferably more flexiblebecause such a polymer becomes easy to physically entangle with thesurfaces of the functional substances and have affinity for them. Theblock polymer is preferably flexible from the viewpoint of easyformation of a coating layer on a recording medium as described indetail below. Therefore, the glass transition temperature Tg of the mainchain of the block polymer is preferably at most 20° C., more preferablyat most 0° C., still more preferably at most −20° C. In this regard, thepolymer having the polyvinyl ether structure is preferably used becauseit has a low glass transition temperature and flexible properties. Sincecoloring materials are preferably used as the functional substances inthe present invention, an aromatic structure, preferably a phenyl orphenylene structure is preferably used in the hydrophobic segment inthat dispersion stability can be improved with higher affinity for them.Further, in order to stabilize the included state, polymers at a corepart, i.e., the hydrophobic segment portion preferably has a certain orstill higher molecular weight, and it is at least 7,000, preferably atleast 10,000, more preferably at least 12,000 in terms of number averagemolecular weight.

As the graft polymer contained in the structured material according tothe present invention may be used a polymer obtained by grafting anacrylic polymer on polyvinyl alcohol, a polymer obtained by grafting apolyvinyl ether polymer on an acrylic polymer or a polymer obtained bygrafting polyester on a methacrylic polymer. A polymer in which agrafting polymer and a grafted polymer have the relation ofhydrophobicity and hydrophilicity, i.e., an amphiphilic polymer ispreferably used.

The content of the block polymer or graft polymer contained in thestructured material according to the present invention is desirably from0.1 to 90% by weight, preferably 0.5 to 80% by weight based on the totalweight of the structured material. When the content of the polymer fallswithin the range of from 0.1 to 90% by weight, the functional substancescontained in the structured material according to the present inventioncan be sufficiently dispersed or included, and the resulting compositioncomes to have a relatively low viscosity suitable for various kinds offunctional materials.

The structured material according to the present invention has a featurethat plural kinds of functional substances are included. The includedstate can be formed by, for example, dissolving coloring materials in anorganic solvent insoluble in water in a micelle formed by the blockpolymer in water. Besides, it can be formed by forming an inclusionstate by conducting phase inversion from a state that both polymer andcoloring materials have been dissolved in an organic solvent into ahydrophilic solvent. It may also be formed by distilling off theremaining organic solvent in such a process. Further, for example, theformation may also be conducted by mixing a dispersion of pigments in awater-insoluble organic solvent with a micelle formed by the blockpolymer in water.

The structured material according to the present invention may be amicelle or reversed micelle formed by the presence of a solvent or thelike as described above, or a structured material formed under such acondition that such a component is not present. The former is preferablyused in the present invention.

The confirmation of the included state can be performed by various kindsof electron microscopes and/or instrumental analyses such as X-raydiffraction. The inclusion in a micelle state, the included state can beindirectly confirmed by separation of the coloring materials from thesolvent under conditions of micelle collapse. As described above, themicelle state is preferably formed by the block polymer. Therefore, theblock polymer used in the present invention is preferably amphiphilic.

The quantitative proportions of the functional substances and polymerincluded in the structured material can also be observed by variouskinds of electron microscopes, instrumental analyses such as X-raydiffraction and/or coloring density analysis of the coloring materials,or by the indirect method described above.

The structured material according to the present invention is preferablyin the form of particles. The particles preferably have an averageparticle diameter of at most 200 nm. When coloring materials are used asthe functional substances, a composition having good tint can berealized when the particle diameter of the particles are small. When thefunctional substance dispersed composition according to the presentinvention is applied to an ink composition, the dispersion stability andtinting strength of a coloring-material-dispersed ink, and brightness ofits color are greatly affected by a particle diameter of dispersedparticles and uniformity of the particle diameter. In other words, whenthe particle diameter of the particles dispersed in the solvent is verygreat, aggregation occurs between the particles, and so stabledispersion may not be achieved in some cases. Since the particlediameter and tinting strength reside in an inversely proportionalrelation (Annalen der Physik, Vol. 25, p. 377, 1908), the tintingstrength may be lowered if the particle diameter is too great.Therefore, the average particle diameter of the particles are preferablyat most 200 nm, more preferably at most 150 nm, still more preferably atmost 100 nm as described above.

The average particle diameter can be measured by various methods.Examples thereof include direct observation through an electronmicroscope, small angle neutron diffraction, small angle X-raydiffraction, light scattering method and laser diffraction. In order tomeasure a particle diameter of particles of a 200-nm or 100-nm level,the measurement can be preferably conducted by a dynamiclight-scattering method. In the present invention, the particle diameterdistribution of the particles can be measured by the dynamiclight-scattering method that is a photon correlation method. As an indexof the uniformity of the particle diameter, is generally used an indexof degree of dispersion indicated by Gulari et al. (The Journal ofChemical Physics, Vol. 70, p. 3965, 1979). The index of degree ofdispersion is preferably at most 0.3, more preferably at most 0.2, stillmore preferably at most 0.1. The smaller the index of degree ofdispersion, the narrower the particle diameter distribution. Particlediameter measuring apparatus by the dynamic light-scattering methodinclude apparatus such as DLS7000 manufactured by Otsuka ElectronicsCo., Ltd.

In the structured material according to the present invention, in whichthe plurality of the functional substances different from each other areincluded in the block polymer or graft polymer, other polymers, andadditives such as surfactants, antioxidants, ultraviolet absorbents andradical-trapping agents may be contained as other components. Thefunctional substance dispersed composition according to the presentinvention will hereinafter be described.

The functional substance dispersed composition according to the presentinvention comprises the functional substance including structuredmaterial, and a solvent or dispersing medium.

The functional substance including structured material contained in thefunctional substance dispersed composition according to the presentinvention is the structured material as described above. The content ofthe structured material in the composition is preferably within a rangeof from 0.01 to 95% by weight, more preferably from 0.1 to 90% by weightbased on the total weight of the composition.

The functional substance dispersed composition according to the presentinvention contains a solvent. No particular limitation is imposed on thesolvent contained in the composition according to the present invention.The solvent means a medium in which components contained in thecomposition can be dissolved, suspended or dispersed. In the presentinvention, organic solvents such as various kinds of linear, branchedand cyclic aliphatic hydrocarbons, aromatic hydrocarbons, andheterocyclic aromatic hydrocarbons, squeous solvents, and water may beused as the solvent. It goes without saying that a mixed solvent thereofmay be used.

In the composition according to the present invention, water andhydrophilic solvents may be suitably used in particular.

Examples of the hydrophilic solvents include polyhydric alcohols such asethylene glycol, diethylene glycol, triethylene glycol, polyethyleneglycol, propylene glycol, polypropylene glycol and glycerol, polyhydricalcohol ethers such as ethylene glycol monomethyl ether, ethylene glycolmonoethyl ether, ethylene glycol monobutyl ether, diethylene glycolmonoethyl ether and diethylene glycol monobutyl ether, andnitrogen-containing solvents such as N-methyl-2-pyrrolidone, substitutedpyrrolidone and triethanolamine. A monohydric alcohol such as methanol,ethanol or isopropanol may also be used. With respect to the pH ofwater, water may be used within all pH ranges. However, the pH ispreferably within a range of from 1 to 14.

The content of the solvent in the composition according to the presentinvention is preferably within a range of from 0.1 to 99% by weight,more preferably from 1 to 95% by weight based on the total weight of thecomposition.

The functional substance dispersed composition according to the presentinvention may also contain a dispersing medium. No particular limitationis imposed on the dispersing medium contained in the composition. Thedispersing medium means a medium, in which components contained in thecomposition can be dispersed. In the present invention, various kinds ofbinder resins, or the like may be used as the dispersing medium inaddition to the solvents described above. In particular, a binder resinmay be suitably used in the composition according to the presentinvention.

The content of the dispersing medium in the composition according to thepresent invention is preferably within a range of from 0.1 to 99% byweight, more preferably from 1 to 95% by weight based on the totalweight of the composition. In the functional substance dispersedcomposition according to the present invention, additives such as othersurfactants than those described above, ultraviolet absorbents,antioxidants, and organic substances such as various radical-trappingagents may also be contained.

The composition according to the present invention can be prepared bymixing the constituent components described above and uniformlydissolving or dispersing the resultant mixture.

The functional substance dispersed composition according to the presentinvention may be preferably used as an ink composition. As a preferredform thereof, may be mentioned an ink-jet ink composition.

The ink composition according to the present invention will hereinafterbe described.

The ink composition comprises the structured material, in which at leasttwo functional substances selected from coloring materials of the sametype or different type are included in the block polymer or graftpolymer.

The content of the block polymer or graft polymer contained in the inkcomposition according to the present invention is within a range of from0.1 to 90% by weight, preferably from 1% by weight to 80% by weightbased on the total weight of the ink composition. In the case where theink composition is used for an ink-jet printer, the content of thepolymer used is preferably from 0.1% by weight to 30% by weight.

Other components than the block polymer of graft polymer contained inthe ink composition according to the present invention will hereinafterbe described in detail.

The other components include water, hydrophilic solvents, coloringmaterials, additives, etc. As described above, organic solvents may alsobe naturally used.

[Water]

As water contained in the composition according to the presentinvention, is preferred ion-exchanged water, purified water or ultrapurewater, from which metal ions and the like are removed.

[Hydrophilic Solvent]

Examples of the hydrophilic solvents include polyhydric alcohols such asethylene glycol, diethylene glycol, triethylene glycol, polyethyleneglycol, propylene glycol, polypropylene glycol and glycerol, polyhydricalcohol ethers such as ethylene glycol monomethyl ether, ethylene glycolmonoethyl ether, ethylene glycol monobutyl ether, diethylene glycolmonoethyl ether and diethylene glycol monobutyl ether, andnitrogen-containing solvents such as N-methyl-2-pyrrolidone, substitutedpyrrolidone and triethanolamine. In order to accelerate drying of thehydrophilic dispersion on a recording medium, a monohydric alcohol suchas methanol, ethanol or isopropanol may also be used.

The content of water and the hydrophilic solvent in the ink compositionaccording to the present invention is preferably within a range of from20 to 99% by weight, more preferably from 30 to 98% by weight based onthe total weight of the ink composition.

[Coloring Material]

Coloring materials such as pigments and dyes are contained in the inkcomposition according to the present invention. Pigments are preferablyused.

The pigments may be either organic pigments or inorganic pigments. Aspigments used in inks, may be used a black pigment and pigments of threeprimary colors of cyan, magenta and yellow. Incidentally, other colorpigments than those described above, colorless or light-colored pigmentsand metalescent pigments may also be used. In addition, pigments newlysynthesized for the present invention may also be used.

Pigments self-dispersible in water may also be used in the compositionaccording to the present invention. The pigments dispersible in waterinclude those making good use of steric hindrance by adsorbing a polymeron the surface of a pigment and those making good use of electrostaticrepulsion force. Examples of commercially available self-dispersingpigments include CAB-O-JET200 and CAB-O-JET300 (both, trade names;products of Cabot Company), and Microjet Black CW-1 (trade name; productof Orient Chemical Industries Ltd.).

When the pigments are used in the ink composition according to thepresent invention, the amount thereof is preferably from 0.1 to 50% byweight based on the total weight of the ink composition. When the amountof the pigments falls within a range of from 0.1 to 50% by weight,sufficient image density is achieved, and the fixing ability of an imageformed becomes good. It is hence preferably to use the pigments in sucha range. A more preferable range of the amount is from 0.5% by weight to30% by weight.

In the ink composition according to the present invention, dyes may alsobe used in place of the pigments or in combination with the pigments.Water-soluble dyes such as direct dyes, acid dyes, basic dyes, reactivedyes and food dyes, and insoluble coloring matter such as oil-solubledyes and disperse dyes may be used.

When the dyes are used in the ink composition according to the presentinvention, the amount thereof is preferably from 0.1 to 50% by weightbased on the total weight of the ink composition. In the ink compositionaccording to the present invention, is used the structured material, inwhich the plural kinds of coloring materials are included in the blockpolymer or graft polymer. By including the plural kinds of coloringmaterials in the polymer, the dispersibility and functionality of therespective coloring materials different in nature can be stabilized. Inthe structured material, in which at least two coloring materials areincluded, the tint can be controlled while realizing excellentdispersion stability by using the plural kinds of coloring materials.

The content of the structured material in the ink composition accordingto the present invention is preferably within a range of from 0.1 to 70%by weight, more preferably from 1 to 50% by weight based on the totalweight of the ink composition.

[Additive]

To the ink composition according to the present invention, variousadditives and auxiliary agents may be added as needed. An example of theadditives includes a dispersion stabilizer, by which a pigment is stablydispersed in a solvent. If dispersion is insufficient, any otherdispersion stabilizer may also be added.

As other dispersion stabilizers, may be used resins or surfactantshaving both hydrophilic portion and hydrophobic portion. Examples of theresin having both hydrophilic portion and hydrophobic portion includecopolymers of a hydrophilic monomer and a hydrophobic monomer.

Examples of the hydrophilic monomer include acrylic acid, methacrylicacid, maleic acid, fumaric acid, monoesters of the carboxylic acidsdescribed above, vinylsulfonic acid, styrenesulfonic acid, vinylalcohol, acrylamide and methacryloxyethyl phosphate. Examples of thehydrophobic monomer include styrene, styrene derivatives such asα-methylstyrene, vinylcyclohexane, vinylnaphthalene derivatives, acrylicacid esters and methacrylic acid esters. The copolymer may be in anyform of random, block and graft copolymers. It goes without saying thatboth hydrophilic monomer and hydrophobic monomer are not limited tothose described above.

As the surfactants, may be used anionic, nonionic, cationic andamphoteric surfactants. Examples of the anionic surfactants includefatty acid salts, alkylsulfate salts, alkylarylsulfonic acid salts,alkyl diaryl ether disulfonic acid salts, dialkylsulfosuccinic acidsalts, alkylphosphonic acid salts, naphthalenesulfonic acid-formalincondensates, polyoxyethylene alkyl phosphate salts and glycerol boratefatty acid esters.

Examples of the nonionic surfactants include polyoxyethylene alkylethers, polyoxyethylene-oxypropylene block copolymers, sorbitan fattyacid esters, glycerol fatty acid esters, polyoxyethylene fatty acidesters, polyoxyethylene alkylamines, fluorine-containing surfactants andsilicon-containing surfactants.

Examples of the cationic surfactants include alkylamine salts,quaternary ammonium salts, alkylpyridinium salts and alkylimidazoliumsalts. Examples of the amphoteric surfactants include alkylbetaines,alkylamine oxides and phosphatidylcholine.

The surfactants are also not limited to those described above.

To the composition according to the present invention, may be added ahydrophilic solvent as needed. When the composition is used as an inkfor ink-jet in particular, the hydrophilic solvent is used for thepurpose of preventing drying of the ink at a nozzle part andsolidification of the ink. Water alone or a mixture of water and anotherhydrophilic solvent may be used. As the hydrophilic solvent, thosementioned above may be used as they are. The content of the hydrophilicsolvent is within a range of from 0.1 to 60% by weight, preferably from1 to 25% by weight based on the total weight of the ink composition.

When the composition is used as, for example, an ink, pH adjustors forachieving stabilization of the ink and stability of the ink to piping ina recording apparatus, penetrants for accelerating penetration of theink into a recording medium to facilitate apparent drying,mildewproofing agents for preventing occurrence of mildew in the ink,chelating agents for blocking metal ions in the ink to preventdeposition of metals at a nozzle part and deposition of insoluble matterin the ink, antifoaming agents for preventing occurrence of foam uponcirculation, transferring or preparation of a recording liquid, andbesides, antioxidants, viscosity modifiers, conductivity-impartingagents, and ultraviolet absorbents may also be added as other additives.Other components than those described above may be contained in the inkcomposition according to the present invention.

The ink composition according to the present invention can be preparedby mixing the constituent components described above and uniformlydissolving or dispersing the resultant mixture. For example, a pluralityof the constituent components are uniformly mixed in a common solvent,the resultant mixture is inversed into a water phase or non-aqueousphase, the phase-inversed mixture is dispersed by means of a sand mill,ball mill, homogenizer, nanomizer or the like to prepare an ink motherliquor, and a solvent and additives are added to this liquor to adjustits physical properties, thereby preparing the ink composition.

A preferred embodiment of the ink composition according to the presentinvention is an ink-jet ink, more preferably an ink corresponding to anOn-Demand type ink-jet. Examples of the On-Demand type ink-jet includethermal and piezo systems. In any case, inks having a low viscosity arerequired. The typical viscosity is at most 10 cp. According to the inkcomposition that is a preferred embodiment of the present invention, thestructured material, in which the coloring materials are included in theamphiphilic block polymer, is dispersed, so that a dispersed state lowin viscosity can be realized. The molecular weight distribution of theblock polymer is preferably made small from the viewpoint of forminguniform micelles.

The average particle diameter of particles composed of thecoloring-material-including block polymer is preferably at most 200 nm.When the average particle diameter is at most 200 nm, good colorexpression can be realized because coloring ability is improved, andlight scattering by visible light can be inhibited.

[Liquid-Ejecting Apparatus]

The liquid-ejecting apparatus according to the present inventioncomprises a liquid-ejecting means for ejecting the composition bycausing energy for ejection to act on the composition, thereby forming apattern, and a driving means for driving the liquid-ejecting means.

A preferred embodiment as a method for forming a pattern using thecomposition is a pattern forming process by an ink-jet method. Apreferred embodiment of the present invention is an image formingprocess comprising the step of forming an image using the ink. The inkaccording to the present invention can be used in image formingapparatus by means of various ink-jet methods. Drawing can be made by animage forming process using this apparatus. The ink-jet method used maybe a well known method such as a piezo ink-jet system using apiezoelectric element or a bubble-jet system that thermal energy isapplied to an ink to cause film boiling to eject the ink, therebyconducting recording. Any type of a continuous type and an On-Demandtype may be used. The ink composition according to the present inventionmay also be used in a recording system that printing is conducted on anintermediate transfer medium with an ink, and an image formed is thentransferred to a final recording medium such as paper.

A pattern of an electron circuit or device may also be formed by thepattern forming process according to the present invention.

A preferred embodiment as a pattern forming apparatus using the patternforming process is an ink-jet recording apparatus using the inkcomposition. This apparatus includes an ink-jet recording apparatus ofthe piezo ink-jet system using a piezoelectric element, the bubble-jetsystem that thermal energy is applied to an ink to cause film boiling toeject the ink, thereby conducting recording, or the like.

FIG. 1 illustrates a schematic mechanism of an ink-jet recordingapparatus according to the present invention. Reference numeral 50indicates a central processing unit (CPU) of the ink-jet recordingapparatus 20. A program for controlling the CPU 50 may be stored in aprogram memory 66 or may also be stored in a memory means such as EEPROM(not illustrated) as the so-called firmware. According to the ink-jetrecording apparatus, recording data from a recording data-preparingmeans (not illustrated, computer or the like) is received by the programmemory 66. The recording data may be information itself of images orcharacters to be recorded, compressed information thereof or encodedinformation. When the compressed or encoded information is processed,expansion or development can be conducted by the CPU 50 to obtain theinformation of the images or characters to be recorded. An X-encoder 62(for example, relating to an X-direction or main scanning direction) anda Y-encoder 64 (for example, relating to a Y-direction or secondaryscanning direction) are provided, whereby a relative position of a headto a recording medium can be notified to the CPU 50.

The CPU 50 sends signals for recording the images to an X-motordrive-circuit 52, a Y-motor drive circuit 54 and a head drive circuit 60on the basis of the information of the program memory 66, X-encoder 62and Y-encoder 64. The X-motor drive circuit 52 and Y-motor drive circuit54 drive an X-direction drive motor 56 and a Y-direction drive motor 58,respectively, to move a head 70 relatively to the recording medium andto a recording position. The head drive circuit 60 sends signals forconducting ejection of the respective ink compositions (Y, M, C and K)and a stimulus-imparting substance, which becomes stimuli, to the head70 at the time the head 70 has been moved to the recording position,thereby conducting recording. The head 70 may be a head for ejecting asingle ink composition or a head for ejecting plural kinds of inkcompositions. The head 70 may have a function for ejecting thestimulus-imparting substance, which becomes stimuli, in combination.

[Head Kit]

An ink-jet head kit having an ink-jet head for ejecting the inkcomposition according to the present invention will be described.

FIG. 2 typically illustrates the ink-jet head kit 500 according to thepresent invention. The ink-jet head kit comprises a kit container 501,and an ink-jet head 510 having an ink-ejecting part 511 for ejecting anink, an ink container 520 that is a liquid container inseparable orseparable from the head 510, and an ink charging means 530 holding anink for charging the ink container, which are contained in the kitcontainer 501.

When the ink has been consumed, it is only necessary to insert a part ofan insertion part 531 (injector needle or the like) of the ink chargingmeans 530 into an air-communicating port 521 of the ink container, or ahole formed in a joint to the ink-jet head or a wall of the inkcontainer so as to charge the ink container with the ink within the inkcharging means 530 through the insertion part. The ink-jet head, inkcontainer, ink charging means and the like are contained in a kitcontainer as described above, whereby the ink can be put immediately andeasily into the ink container as described above even when the ink hasbeen consumed, so as to rapidly start recording.

Incidentally, description has been given to the ink-jet head kitcontaining the ink charging means. However, the ink-jet head kitaccording to the present invention may be in such a form that no inkcharging means is provided, but a separable type ink container, whichhas been charged with ink, and a head are contained in a kit container510.

Although only the ink charging means for charging the ink container withink is illustrated in FIG. 2, the ink-jet head kit may be in such a formthat a foaming liquid charging means for charging a foaming liquidcontainer with a foaming liquid is contained in addition to the inkcharging means in the kit container.

The present invention will hereinafter be described in detail by thefollowing examples. However, the present invention is not limited tothese examples.

EXAMPLE 1

<Synthesis of Block Polymers>

Synthesis of an AB block polymer terminated by a carboxylic acid one anend composed of isobutyl vinyl ether (IBVE), 2-methoxyethyl vinyl ether(MOVE) and HO(CH₂)₅COOH.

A poly[IBVE-b-MOVE]-O(CH₂)₅COOH (here, b is a symbol indicating a blockpolymer) was synthesized in accordance with the following procedure.After the interior of a glass container equipped with a three-waystop-cock was purged with nitrogen, the container was heated to 250° C.under a nitrogen gas atmosphere to remove adsorbed water. After thesystem was returned to room temperature, 12 mmol of IBVE (component A),16 mmol of ethyl acetate, 0.1 mmol of 1-isobutoxyethyl acetate and 11 mlof toluene were added to cool the reaction system. At the time thetemperature within the system had reached 0° C., 0.2 mmol ofethylaluminum sesquichloride (equimolar mixture of diethylaluminumchloride and ethylaluminum dichloride) was added to initiatepolymerization. The molecular weight was monitored with a time-divisioninterval by means of gel permeation chromatography (GPC) to confirmcompletion of the polymerization of the component A.

Then, 12 mmol of a component B (MOVE) was added to conductpolymerization. After completion of the polymerization of the componentB was confirmed by monitoring by means of GPC, 30 mmol of HO(CH₂)₅COOEtwas added to terminate the polymerization reaction. The reaction mixturesolution was diluted with dichloromethane and washed three times with0.6 M hydrochloric acid and then three times with distilled water. Theresultant organic phase was concentrated and dried to solids by anevaporator to obtain a block polymer of poly[IBVE-b-MOVE]-O(CH₂)₅COOEt.

The identification of the compound synthesized was conducted by means ofGPC and NMR. The identification of a portion bonded to a terminal wasconducted by confirming the presence of a terminal site in a spectrum ofthe high-molecular weight compound by measurement by means of the DOSYmethod of NMR. Mn was 2.2×10⁴, and Mw/Mn was 1.2. Mn denotes a numberaverage molecular weight, and Mw indicates a weight average molecularweight. The ester portion at the terminal of thepoly[IBVE-b-MOVE]-O(CH₂)₅COOEt thus obtained was hydrolyzed, and theresultant product was identified by NMR. As a result, it was found thatthe intended poly[IBVE-b-MOVE]-O(CH₂)₅COOH was obtained.

Twenty-six parts by weight of the carboxylic acid-terminated blockpolymer was stirred together with 200 parts by weight of an aqueoussolution of sodium hydroxide having a pH of 10 at 0° C. for 3 days toprepare a solution of a sodium salt of the carboxylic-acid-containingpolymer, in which the polymer had been completely dissolved. The polymerwas extracted from methylene chloride, the extract was dried, and thesolvent was distilled off to isolate the polymer.

Twenty-five parts by weight of this polymer, 5 parts by weight of afat-soluble dye, Oil Blue N (trade name, product of Aldrich Co.) and 5parts by weight of a fat-soluble dye, Valifast Yellow (trade name,product of Orient Chemical Industries Ltd.) were dissolved in 50 partsby weight of THF, and the resultant solution was then added dropwise to800 parts by weight of distilled water with stirring. Fifty parts byweight of ethylene glycol was additionally added. The resultant mixturewas left to stand at 40° C. for 3 hours in an open condition from thisstate, and THF was completely distilled off to prepare a green inkcomposition (1) according to this example. The particle diameter of theink composition was measured by means of a particle diameter measuringapparatus, DLS7000 (trade name; manufactured by Otsuka Electronics Co.,Ltd.). As a result, the average particle diameter was 96 nm, and theindex of degree of dispersion was 0.089.

EXAMPLE 2

The ink prepared in EXAMPLE 1 was put in an ink tank of a BJ PrinterS530 (trade name, manufactured by Canon Inc.) to conduct recording onplain paper. As a result, green characters were printed beautifully.

EXAMPLE 3

A green ink composition (2) was prepared in the same manner as inEXAMPLE 1 except that the component A of the block polymer used inEXAMPLE 1 was changed to 2-ethoxyethyl vinyl ether. The polymer of2-ethoxyethyl vinyl ether that is the component A was changed from thatof hydrophobicity to hydrophilicity at a temperature not higher than 20°C., and the micelle was collapsed at the time the polymer becamehydrophilic. The ink composition (2) was cooled to 0° C. to collapse themicelle. As a result, the coloring materials were dissolved out andsurfaced on an upper part of the ink. The water phase was completelydecolored. By this fact, it was confirmed that the coloring materialswere completely included in the block polymer micelle. With respect tothe coloring material concentration-ratio of the ink composition (2) tothe decolored water phase in terms of an intensity ratio at λ_(max), thelatter was 0.4% of the former, so that it was found that at least 99% ofthe coloring materials were included.

COMPARATIVE EXAMPLE 1

The two fat-soluble dyes used in EXAMPLE 1 were dissolved in methylenechloride, the resultant solution was applied on plain paper by a brush.The plain paper was left to stand for 30 hours under an environmentcontaining 10 ppm of ozone. Change in OD was compared with the recordingmedium in EXAMPLE 2 by means of a particle diameter measuring apparatusRD-19 (trade name, manufactured by Sakata Ink K.K.). As a result, thereduction rate was 3 times as much as EXAMPLE 2.

EXAMPLE 4

Ten parts by weight of the polymer prepared in EXAMPLE 1, 3 parts byweight of a fat-soluble dye, Oil Yellow (trade name, product of OrientChemical Industries Ltd.) and 4 parts by weight of a fat-soluble dye ofthe same hue, Valifast Yellow (trade name, product of Orient ChemicalIndustries Ltd.) were dissolved in 50 parts by weight of THF, and theresultant solution was then added dropwise to 700 parts by weight ofdistilled water with stirring. Fifty parts by weight of ethylene glycolwas additionally added. The resultant mixture was left to stand at 40°C. for 3 hours in an open condition from this state, and THF wascompletely distilled off to prepare an ink composition with particlesuniformly dispersed without deposits.

The particle diameter of the ink composition was measured by means of adynamic light-scattering measuring apparatus, DLS7000 (trade name;manufactured by Otsuka Electronics Co., Ltd.). As a result, the averageparticle diameter was 98 nm, and the index of degree of dispersion was0.097. Even when the ink composition was left to stand at roomtemperature for 2 months, no deposit was observed, and the dispersionwas stable. The ink was put in an ink tank of a BJ Printer S530 (tradename, manufactured by Canon Inc.) to conduct recording on plain paper.As a result, characters were printed beautifully.

COMPARATIVE EXAMPLE 2

Ten parts by weight of sodium polyacrylate (number average molecularweight Mn: 6,000), 3 parts by weight of a fat-soluble dye, Oil Yellow(trade name, product of Orient Chemical Industries Ltd.) and 4 parts byweight of a fat-soluble dye of the same hue, Valifast Yellow (tradename, product of Orient Chemical Industries Ltd.) were dissolved in 50parts by weight of THF, and the resultant solution was then addeddropwise to 700 parts by weight of distilled water with stirring. Fiftyparts by weight of ethylene glycol was additionally added. The resultantmixture was left to stand at 40° C. for 3 hours in an open conditionfrom this state, and THF was completely distilled off to prepare an inkcomposition. As a result, a comparative amount of deposit was observed.Therefore, coarse particles were removed by a membrane filter having apore size of 2 μm to prepare an ink composition. When the inkcomposition was left to stand at room temperature for 1 month, yellowdeposits were observed.

COMPARATIVE EXAMPLE 3

Ten parts by weight of a block polymer (polymerization ratio:styrene/acrylic acid=6/4; Mn: 12,000) of styrene and sodium acrylate and7 parts by weight of a fat-soluble dye, Oil Yellow (trade name, productof Orient Chemical Industries Ltd.) were dissolved in 50 parts by weightof THF, and the resultant solution was then added dropwise to 700 partsby weight of distilled water with stirring. Fifty parts by weight ofethylene glycol was additionally added. Coarse particles were removed bya membrane filter having a pore size of 2 μm to prepare an inkcomposition. When the ink composition was left to stand at roomtemperature for 1 month, yellow deposits were observed.

EXAMPLE 5

A polymer using 2-(4-methylphenyl)ethyl vinyl ether as a segment A,2-(2-methoxyethyloxy)ethyl vinyl ether as a segment B and ethyl4-(2-vinyloxy)ethoxybenzoate as a segment C having a copolymerizationratio A/B/C of 90/80/14 was synthesized in the same manner as inEXAMPLE 1. The number average molecular weight of a polymer of thecomponent A alone was 12,700, and Mw/Mn was 1.09. The number averagemolecular weight of the ABC block polymer was 24,400, and Mw/Mn was1.31. As with EXAMPLE 4, 10 parts by weight of this polymer, 5 parts byweight of a fat-soluble dye, Oil Yellow (trade name, product of OrientChemical Industries Ltd.) and 4 parts by weight of a fat-soluble dye ofthe same hue, Valifast Yellow (trade name, product of Orient ChemicalIndustries Ltd.) were dissolved in 50 parts by weight of THF, and theresultant solution was then added dropwise to 700 parts by weight ofdistilled water with stirring. Fifty parts by weight of ethylene glycolwas additionally added. The resultant mixture was left to stand at 40°C. for 3 hours in an open condition from this state, and THF wascompletely distilled off to prepare an ink composition with particlesuniformly dispersed without deposits.

The particle diameter of the ink composition was measured by means of adynamic light-scattering measuring apparatus, DLS7000 (trade name;manufactured by Otsuka Electronics Co., Ltd.). As a result, the averageparticle diameter was 61 nm, and the index of degree of dispersion was0.074. Even when the ink composition was left to stand at roomtemperature for 2 months, no deposit was observed, and the dispersionwas stable. The ink was put in an ink tank of a BJ Printer S530 (tradename, manufactured by Canon Inc.) to conduct recording on plain paper.As a result, characters were printed beautifully.

EXAMPLE 6

An investigation was made in the same manner as in EXAMPLE 5 using thepolymer prepared in EXAMPLE 5 except that 5.parts by weight of PigmentYellow 128 was used in place of 5 parts by weight of the fat-solubledye, Oil Yellow (trade name, product of Orient Chemical IndustriesLtd.). In this case, an ink composition with particles uniformlydispersed without deposits was obtained. The particle diameter of theink composition was measured by means of a dynamic light-scatteringmeasuring apparatus, DLS7000 (trade name; manufactured by OtsukaElectronics Co., Ltd.). As a result, the average particle diameter was126 nm, and the index of degree of dispersion was 0.082. Even when theink composition was left to stand at room temperature for 2 months, nodeposit was observed, and the dispersion was stable. The ink was put inan ink tank of a BJ Printer S530 (trade name, manufactured by CanonInc.) to conduct recording on plain paper. As a result, characters wereprinted beautifully.

EXAMPLE 7

An investigation was made in the same manner as in EXAMPLE 5 using thepolymer prepared in EXAMPLE 5 except that 3.5 parts by weight of carbonblack, MOGUL L (product of Cabot Company) was used in place of 5 partsby weight of the fat-soluble dye, Oil Yellow (trade name, product ofOrient Chemical Industries Ltd.), and 1.5 parts by weight of an blackfat-soluble dye, Oil Black HBB (trade name, product of Orient ChemicalIndustries Ltd.) was used in place of 4 parts by weight of thefat-soluble dye, Valifast Yellow (trade name, product of Orient ChemicalIndustries Ltd.). In this case, an ink composition with particlesuniformly dispersed without deposits was obtained. The particle diameterof the ink composition was measured by means of a dynamiclight-scattering measuring apparatus, DLS7000 (trade name; manufacturedby Otsuka Electronics Co., Ltd.). As a result, the average particlediameter was 132 nm, and the index of degree of dispersion was 0.099.Even when the ink composition was left to stand at room temperature for3 months, no deposit was observed, and the dispersion was stable. Theink was put in an ink tank of a BJ Printer S530 (trade name,manufactured by Canon Inc.) to conduct recording on plain paper. As aresult, characters were printed beautifully.

COMPARATIVE EXAMPLE 4

An ink composition was prepared in the same manner as in EXAMPLE 7except that the black fat-soluble dye, Oil Black HBB (trade name,product of Orient Chemical Industries Ltd.) used in the preparation ofthe ink composition in EXAMPLE 7 was not used. When this ink was left tostand at room temperature for 3 months, it was observed that the pigmentwas slightly precipitated on the bottom of a sample bottle.

Since the functional substance including structured material accordingto the present invention has a plurality of functional substancesdifferent from each other included in a polymer, its dispersionstability is good, and the composition containing the structuredmaterial and a solvent inhibits aggregation by interaction betweenparticles, has stable dispersibility in the solvent and can be utilizedas an ink composition having good coloring ability and fixing ability.The ink composition can be stably applied from an ink-applying apparatusto conduct printing on a recording medium, and can be utilized as an inkcomposition for the ink-applying apparatus.

This application claims priority from Japanese Patent Application Nos.2003-286926 filed Aug. 5, 2003 and 2004-216363 filed Jul. 23, 2004,which are hereby incorporated by reference herein.

1. A structured material including functional substances, comprising aplurality of different functional substances physically included in ablock polymer or graft polymer.
 2. The structured material according toclaim 1, wherein the plurality of different functional materials areincluded in a micelle formed by the block polymer or graft polymer. 3.The structured material according to claim 1, wherein the plurality ofdifferent functional materials are at least two substances selected fromfunctional substances.
 4. The structured material according to claim 1,wherein the plurality of different functional materials are at least twosubstances selected from coloring materials.
 5. The structured materialaccording to claim 4, wherein at least one of the coloring materials isan oil-soluble dye or pigment.
 6. The structured material according toclaim 1, wherein the structured material is in the form of particles,and the average particle diameter of the particles is at most 200 nm. 7.The structured material according to claim 1, wherein the block polymerhas a polyalkenyl ether repeating unit structure.
 8. Afunctional-substance-dispersed composition comprising the structuredmaterial including functional substances according to claim 1, and asolvent or dispersing medium.
 9. A liquid-applying process comprisingthe step of applying the functional-substance-dispersed compositionaccording to claim 8 to a medium.
 10. A liquid-applying apparatuscomprising a liquid-applying means for applying thefunctional-substance-dispersed composition according to claim 8 bycausing energy for application to act on the composition, and a drivingmeans for driving the liquid-applying means.